Answer:
Explanation:
When the body senses foreign substances (called antigens), the immune system works to recognize the antigens and get rid of them. B lymphocytes are triggered to make antibodies (also called immunoglobulins). These proteins lock onto specific antigens.
D beacuse i know that from past experiance
Pandemics, diseases which spread to most populated regions with a high degree of mortality, have been recorded several times in world history, the first being the Plague of Justinian in 541 CE. The Black Death, also known as the Second Pandemic, was one of the most catastrophic events in human history.
Testing facilities that engage in animal testing dispose of both animals and dangerous chemicals, food waste, and a variety of supplies used during the testing process. Not to mention, animal testing has a heavy impact on water and air quality. Additionally, animal testing is cruel and ineffective. Animals don't get many of the diseases that humans do. For example, major types of heart disease, many types of cancer, HIV, Parkinson's disease, and schizophrenia. 100 million animals are killed each year due to animal testing.
